Question

(3/4 - 4y).(4y + 3/4)​

Answer 1

Explicação passo-a-passo:

$\left(\dfrac{3}{4}-4y\right)\cdot\left(4y+\dfrac{3}{4}\right)$ é o mesmo que:

$\left(\dfrac{3}{4}-4y\right)\cdot\left(\dfrac{3}{4}+4y\right)$

Lembre-se que:

$(a-b)\cdot(a+b)=a^2-b^2$

Assim:

$\left(\dfrac{3}{4}-4y\right)\cdot\left(\dfrac{3}{4}+4y\right)=\left(\dfrac{3}{4}\right)^2-(4y)^2$

$\left(\dfrac{3}{4}-4y\right)\cdot\left(\dfrac{3}{4}+4y\right)=\dfrac{9}{16}-16y^2$